I'll let you know when it's going to be fast again, it's a priority for me.

After some optimizations I did today analysing Drupal core now finishes in around 3 minutes on my computer.

Please try PHPStan 1.8.5 once I release it and report back.

BTW I tried to do something about the big difference between 1.5.7 and 1.6.0 to figure out if there's more space for some other optimizations, but sadly PHPStan 1.5.7 cannot analyse Drupal core successfully, there's some code (incompatible method signatures between parent and child) that makes it crash. On PHPStan 1.7.0+ this isn't a problem thanks to static reflection, but I can't verify the same slowdown between 1.5.7 and 1.6.0 you have seen because of this problem.

@mondrake Hey, I just learn something super-interesting. I was able to make analysis of Drupal codebase several times faster by enabling bleedingEdge:

includes:
    - phar://phpstan.phar/conf/bleedingEdge.neon

On my computer, with the fresh checked-out repo, it takes 3m51s to analyze the whole codebase. In GitHub Actions, it's not able to finish in 30m.

With bleedingEdge, on my computer it takes 1m15s to analyze the whole codebase. In GitHub Actions, it finishes in 5m38s (and that includes cloning the repo and composer install 🐵)

And also it consumes only about 50 % of memory.

The reason is probably this: https://phpstan.org/blog/phpstan-1-6-0-with-conditional-return-types#lower-memory-consumption

Thanks to no memory cycles, the garbage collector has nothing to worry about so it doesn't spend CPU cycles searching for any memory to free up.